Field of the Invention
The present invention relates to the control of a remote electronic device, for example a hand-held tablet-computer, with a local electronic device, for example a smartphone. The invention is particularly useful if the remote device has a larger screen than the local device.
Description of the Prior Art
During the last decade, a significant increase in the number of mobile devices such as smartphones and hand-held tablets has been observed around the world. There is also a growing interest in using mobile devices to control other electronic devices, for example electrical systems in homes, medical appliances, robots or gaming consoles.
Several existing products, such as TeamViewer®, allow users to remotely control a remote device from a local device. After the user has installed a program on both devices, the user can remotely control, for example, his desktop or tablet computer at home from his smartphone and access the files, pictures, applications and programs stored on the computer from the mobile device. Usually, the screen of the local device displays a complete or partial copy of the content that is displayed on the screen of the remote device. This gives the user the feeling as if he was looking at the screen of the remote device.
Simultaneously, inputs on the local device are interpreted as being destined for the remote device. In this remote mode, the commands corresponding to the user inputs are transmitted to the remote device via a communication channel. On the remote device, these commands are executed as if they had been input at the remote device. It is also possible to provide somebody else, for example an IT specialist, with an access to one's own device for repair or maintenance work on the software running on that device.
Some products of this kind provide the option to (temporarily) switch to a local mode. In this local mode, all or certain user inputs are interpreted to be destined for the local device, although the communication channel to the remote device is established. This implies that commands corresponding to these inputs are not transmitted to the remote device, but are executed on the local device. For example, a user may wish to change certain settings of his local device, or to reboot the local device, but not the remote device. This can be done only in the local mode, because in the remote mode such commands would be executed by the remote device. Switching from the remote mode to the local mode, and back from the local mode to the remote mode, usually requires a specific user input, for example pushing a soft button that is produced by the program and overlays the screen content of the local device.
If the screen of the local device is smaller than the screen of the remote device, it is necessary to display on the local device a scaled down copy of the screen content of the remote device. Only then the user can visually capture the entire content of the remote screen instantly. However, decreasing the image size is possible only within certain limits. A large reduction of the image size entails that text and other features may become too small to be legible.
Furthermore, in the case of a local device having a touch-sensitive screen, it may become difficult for a user to hit the links or soft buttons with his fingertip or a pen. Under such circumstances, the user often magnifies the screen content of the local device. To this end, the user has to switch to the local mode, because it is not desired to magnify the content of the remote screen, but its copy on the local screen.
Although a magnification of the screen content of the remote screen also leads to an increased feature size on the screen of the local device, the result is not the same. For example, if a map is displayed on the remote device, an increased magnification of the remote screen content usually implies that the map is displayed with an increased scale. In many maps, the size of texts and similar map features remains the same, but additional features are added.
Similar considerations also apply to scroll movements. For example, scrolling over a map on the local device entails that the user can visually capture the entire map shown on the remote screen successively. If the map is scrolled directly on the remote screen, this implies that certain parts of the map cannot be displayed on the local device any more, while new parts of the map are added.
After the user switches to the local mode, it is usually necessary to manually switch back to the remote mode in which all user inputs are transmitted to the remote device again.
After a magnification of the local screen content, the entire screen content of the remote device cannot be displayed on the local device any more. Then the user must scroll the screen content for being able to visually capture the entire content of the remote screen successively. If the local device has a touch-sensitive screen, scrolling is usually controlled by a pan gesture of a fingertip or a pen. But if such scroll commands shall be executed on the local screen and not on the remote screen, the user must again switch from the remote to the local mode. This requires an additional user input.
Therefore, in situations in which the local screen is smaller than the remote screen, the user interface becomes complicated, because the user must frequently switch between the local mode and the remote mode.